CHAPTER 5 Biological Diversity and Conservation Penguins are

CHAPTER 5: Biological Diversity and Conservation

Penguins are flightless birds living in the southern hemisphere. Contrary to popular belief, they are not found in only cold climates, such as Antarctica. The largest species average about 1. 1 meters (3 ft 7 in) tall and weigh 35 kilograms (75 lb) or more. The smallest penguin species stands around 40 cm tall (16 in) and weighs 1 kilogram (2. 2 lb). Generally larger penguins retain heat better and inhabit colder regions, while smaller penguins are found in temperate or even tropical climates. and will occasionally cross the equator while feeding.

5. 1 Vanishing Species A. Biodiversity = the variety of organisms (number of different species) in a given area 1. Where is Biodiversity Found? Terrestrial biodiversity tends to increase as you move towards the equator. Ex: Tropical regions contain 2/3 of all land species.

• Large islands tend to have greater biodiversity than small islands Hence, la Hispaniola has more biodiversity than Puerto Rico which has more diversity than Aruba.

B. Importance of Biodiversity 1. Importance to Nature -Organisms are adapted to living in communities. (habitat, niche, food chain, food web, symbiotic relationships, predators necessary to maintain carrying capacity) -Biodiversity brings stability 2. Importance to People -dependent on other organisms for needs: O 2, CO 2 removed, diverse diet, clothes, furniture, buildings, pharmaceuticals.

C. Loss of Biodiversity -extinction: disappearance of a species -threatened species: population of a species begins declining rapidly -endangered species: numbers become so low that extinction is Possible -hunting: entire species can become endangered or extinct from excessive hunting for food or other products -Critical because of the interactions of ecosystems. Unbalance could cause a collapse.

D. Threats to Biodiversity 1. Habitat Alteration / Fragmentation – Natural habitats can be destroyed from developing land – The habitats can be broken up into patches of natural habitat surrounded by developed land (fragmentation) biotic issues: predation/reestablishment abiotic issues: edge effect

2. Habitat Degradation Pollution: -Air: - The Ozone Layer (O 3) is toxic at ground level but necessary in the Earth’s atmosphere. • It shields the biosphere from UV Radiation from the sun, which is known to cause cancer, damage eyes, and harm plant tissue and phytoplankton. • CFC’s (Chlorofluorocarbons) react with this vital atmospheric layer and allow UV Rays to break apart ozone molecules • Acid Precipitation: from greatest source of pollution … the burning of fossil fuels

-Water: -fertilizer, animal waste get into runoff Algal Bloom -eroded soil – clogs gills -Detergent , metals, industrial chemicals in runoff -Drift nets abandoned NOTE: THE EXCESS NUTRIENTS IN RUNOFF CAN CAUSE EUTROPHICATION: Having waters rich in mineral and organic nutrients that promote a proliferation of plant life, especially algae, which reduces the dissolved oxygen content and often causes the extinction of other organisms.

BIOMAGNIFICATION Pollution from oil, pesticides like DDT, and other chemicals have caused a major decrease in Biodiversity. The concentration of these pollutants inside animals increases as it travels up a food chain: Biological Magnification

3. Introduction of Exotics -harmless foreign plants and animals are introduced into an ecosystem -These new organisms have little competition and thrive in their new environments, devastating other life in the ecosystem.

5. 2 Conservation of Biodiversity Conservation: studies methods and implements plans to protect biodiversity 1. Legal protection of species: US Endangered Species Act 2. Preserving Habitats – -establishing parks and protected areas -sustainable use -habitat corridors 3. Reintroduction Programs -Captivity